The number of emergency-room visits involving abuse of prescription drugs such as Xanax, Valium and Ativan has skyrocketed 111 percent from 2004 through 2010, a new city Health Department analysis has found.

That’s 6,555 emergency-room visits.

The number of overdose deaths from the anti-anxiety/sleeping pills also jumped 18 percent over five years, to 226. These cases accounted for 44 percent of all overdose deaths.

White, mostly middle-class residents are the biggest abusers of the sedatives.

Staten Island has the highest overdose-death rate in the city and the largest rate of teens who misuse these prescription drugs — 1.2 percent — nearly double the rate of the other boroughs.

Sam G., a 20-year-old recovering addict from Great Kills in treatment at the Camelot Counseling Centers program in the Port Richmond section, said Xanax nearly destroyed his life.

“Xanax is a substance that completely changes you. You say and do things you would never do,” he said.

“Xanax had me conducting criminal behavior. My life spiraled out of control.”

Sam, who admits hitting rock bottom after stealing from a family member, said he’s on the road back to a drug-free lifestyle.

In light of the scourge, city health officials vowed to ratchet up the city’s public-awareness campaign against prescription-drug abuse.

Meanwhile, a new state law tightens the monitoring of doctors and pharmacists who prescribe such drugs.

“The perception that prescription-drug misuse is safe is unfortunate and dangerous,” said Adam Karpati, the Health Department’s executive deputy commissioner.

Drug-treatment experts said the use of sedatives started innocently enough in the 1970s, when Valium, for instance, was referred to as “Mother’s Little Helper” to help ease anxiety.

The ease of obtaining these drugs via prescriptions, the medicine cabinet and the Internet has fueled an addiction epidemic, said Deni Carise, chief clinical officer of Phoenix House treatment centers.